计算机与软件工程学院编码密码系列学术报告

报告人：温金明、张俊、赵山程

报告时间：2023年5月15日14:00-18:00

报告地点：6A519

主办单位：计算机与软件工程学院

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题目1：A ReLU-based Hard-thresholding Algorithm for Non-negative Sparse Signal Recovery

报告人简介：

 温金明，暨南大学教授、博导、国家高层次青年人才、广东省青年珠江学者，主持国家自然科学基金面上项目2项，省级项目4项；2015年6月博士毕业于加拿大麦吉尔大学数学与统计学院。从2015年3月到2018年9月，温教授先后在法国科学院里昂并行计算实验室、加拿大阿尔伯塔大学、多伦多大学从事博士后研究工作。温教授的研究方向是整数信号和稀疏信号恢复的算法设计与理论分析，以第一作者/通讯作者在Applied and Computational Harmonic Analysis、IEEE Transactions on Information Theory、 IEEE Transactions on Signal Processing等期刊和会议发表50余篇学术论文。

报告内容简介：

In numerous applications, such as DNA microarrays, face recognition and spectral unmixing, we need to acquire a non-negative K-sparse signal x from an underdetermined linear model y= Ax+v. To recover such sparse signals, we propose a ReLU-based hard-thresholding algorithm (RHT) and then develop two sufficient conditions of stable recovery with RHT, which are respectively based on the restricted isometry property (RIP) and mutual coherence of the sensing matrix A. As far as we know, these two sufficient conditions are the best for hard-thresholding-type algorithms. Finally, we perform extensive numerical experiments to show that RHT has better overall recovery performance and more efficient than the non-negative least squares (NNLS) algorithm, some hard-thresholding-type algorithms including the iterative hard-thresholding (IHT) algorithm, hard-thresholding pursuit (HTP), Newton-step-based iterative hard-thresholding algorithm (NSIHT) and Newton-step-based hard-thresholding pursuit (NSHTP), and Non-Negative orthogonal matching pursuit (NNOMP), Fast NNOMP (FNNOMP) and Support-Shrinkage NNOMP (SNNOMP), which are variants of orthogonal matching pursuit (OMP) for recovering non-negative sparse signals.

题目2：Reed-Solomon码的深洞及相关问题

报告人简介：

 张俊，首都师范大学数学科学学院研究员，主要研究方向为编码理论与密码学。本科毕业于南开大学陈省身数学试点班，博士毕业于南开大学陈省身数学研究所，曾获留学基金委资助赴美国加州大学欧文分校联合培养，以及美国俄克拉荷马大学学术访问。在国内外学术期刊Math. Ann.、IEEE Trans. Inf. Theory、IEEE TCOM、Finite Fields Appls、中国科学：数学以及国际会议IEEE ISIT等上发表论文三十余篇。主持国家自然科学基金优青项目、面上项目、青年项目等。

报告内容简介：

计算编码的覆盖半径是编码理论的基本问题之一，目前已知覆盖半径的经典线性码码类很少，广义Reed-Solomon码是其中一类。与编码的错误距离达到覆盖半径的向量称为深洞，广义Reed-Solomon码的深洞就是距离所有低次多项式(不超过k-1次)最远的曲线对应的向量。在报告中，我们将采用有限几何的语言介绍广义Reed-Solomon码的深洞以及相关的组合、计算等问题。

题目3：多维耦合空间耦合乘积码

报告人简介：

  Shancheng Zhao， received the bachelor's degree in software engineering and Ph.D. degree in communication and information systems from Sun Yat-sen University, Guangzhou, China, in 2009 and 2014, respectively. From 2013 to 2014, he was a Graduate Visiting Student with the University of California at Los Angeles, Los Angeles, CA, USA. He is currently a Professor with the College of Information Science and Technology, Jinan University, Guangzhou. His current research interests include spatially coupled codes and their applications. He was a co-recipient of the Best Paper Award at the IEEE GlobeCom in 2015 and the 2021 Natural Science Award of the Chinese Institute of Electronics. He serves as an Associate Editors for IET Quantum Communication, Physical Communication (Elsevier), and Alexandria Engineering Journal.

报告内容简介：

本报告提出一类面向高速光通信的空间耦合乘积类码（Spatially Coupled Product-Like Codes）--多链拉链码（Multichain Zipper Code，MC-ZC）。我们将概述光通信编码的发展历程，介绍MC-ZC的编码和译码流程，分析MC-ZC的最小Stall pattern。我们的分析结果表明，MC-ZC的最小Stall pattern大于Zipper码的最小Stall pattern。最后，我们将给出大量仿真验证MC-ZC的性能优势。